This invention applies to the field of fiber optics, and more particularly to the termination of light guides in the form of luminaires that control the distribution of light emitted from the end of a fiber optic light guide. Presently known fiber optic light guides are terminated simply by cutting the emitting ends flat and normal to the centerline. Since the emitted beam will be distorted by an irregular cut, users polish the fiber ends. Some users of plastic fibers flatten the end surface of the fibers against a smooth surface heated to the melting point of the plastic, forming a miniature flat rivet head on the end of the fiber.
Except for decorative and accent lighting, or for endoscopy, fiber optic light guides are rarely used for area lighting or task illumination. Since glass fiber light guides are extremely expensive and tint the light green, plastic fibers are the only material that is practical for illumination. However, illuminators capable of feeding illumination level light into plastic light guides have not been available, as the plastic fibers melt or burn in the intense focused heat of the illuminator lamps. The inventor of this present invention has solved this chronic prior art problem through a new fiber optic illuminator described and shown in my patent application Ser. No. 07/681,732, U.S. Pat. No. 5,099,399. The availability of this illuminator has now created a need for fiber optic luminaires, typical of the present invention, that direct and control the emitted light from the light guides to perform useful area and task illumination.
The disadvantage of single fiber or bundled fiber prior art arrays is that the light is emitted like a floodlight having a wide conical beam spread a beam spread-to-distance ratio of greater than 1:1, wherein a bundle of fibers in a normal eight-foot-high coiling would have a pattern on the floor that is more than ten feet in diameter. In order to effectively illuminate an object on display, or a task such as reading, the ceiling height distance would require the light guide to emit light in the pattern of a narrow-beam spotlight, which is unknown in the current art.
The basic purpose of the present invention is to provide a fiber optic light guide luminaire having narrow-beam spotlight candlepower distribution. It is a further purpose of the invention to provide a fiber optic light guide luminaire which is easily installable with minimum labor, and in which the light guide or even a single fiber can be easily replaced if broken or damaged.